Effect of glucose and water transport by a glucose polymer in rat small intestine

When children with diarrhea are fed oral 5% glucose solutions, exacerbation of symptoms may recur. An orally administered synthetic polymer consisting of amylose and amylopectin will have a lower intraluminal intestinal solute content than 5% glucose and thus might avoid this problem. To evaluate this hypothesis in 53 adult rats, a 5cm length of isolated duodenum in continuity with its blood supply was utilized to instill equivalent amounts of polymer or 5% glucose. A saline control was also used. The succus entericus (SE) was removed at 3', 15', 30' and 60' after instillation and the duodenal mucosa excised. At 3', 15' and 30', the osmolality of the SE after polymer was significantly lower than after 5% glucose solution of saline. At 60', this difference disappeared despite a persistent elevation in SE glucose after 5% glucose. A 4 fold increase of intramucosal glucose over SE glucose was apparent after polymer but not with 5% glucose or saline, suggesting enhanced absorption. The latter finding may be related to the observed stimulatory effect of the polymer on pancreatic amylase secretion. Evaluation of intramucosal water and electrolytes revealed no major mucosal to luminal shifts in fluid. These observations of reduced luminal solute and enhanced glucose absorption with a synthetic polymer suggest advantages to such a preparation over 5% glucose solution in the per oral nutritional management of children with upper gastrointestinal dysfunction.